Why do people keep on putting really old photos of themselves in communications?

Whether it is in a bio, a realtors' business card, or an online profile, so many people put a photo which is ten years old. I know that it is impossible to keep totally up to date. Even when we have one taken fresh for the purpose, it gets old fast. However, I have seen many which are so old that I do not recognize the person when I meet them. This is totally counterproductive and really rather sad.